The present invention relates generally to an automated manufacturing system and more particularly relates to a method and an apparatus for manufacturing optical lenses to order in an efficient, high-speed manner.
The traditional manufacturing and distribution chain for a lens used in consumer eyeglasses generally includes a manufacturer, a laboratory, and a retail outlet. The manufacturer typically makes a lens blank and then ships the blank to the laboratory. The blank is an unfinished lens. The laboratory generally surfaces and edges the lens in the appropriate fashion for a given prescription and then ships the lens to the retail outlet. The retail outlet cuts and fits the lens to the appropriate frame. The retail outlet is generally a doctor or an eye care outlet. The retail outlet both orders the lens from the laboratory or the manufacturer and then fits the lens and the frame as appropriate for the consumer.
Any of the parties in the manufacturing and distribution chain may stockpile certain types of lenses. Certain common prescriptions may be manufactured in bulk and kept in supply. In most cases, these lenses are single vision lenses, i.e., lenses with only one viewing power. Other types of prescriptions, however, may not be as common and may be made only on an as-needed basis. Further, other types of lenses, such as progressive lenses (bi-focal lenses without lines) are generally made on demand given the differing strengths involved in the single lens. In other words, the progressive lens will have surfaces of different curvature as required for distance and reading.
These specialty lenses generally are more expensive in that the manufacturing process is both time and labor intensive. Further, these lenses cannot be easily inventoried because of the multiple permutations of strengths in a given lens. This is particularly due to the condition of astigmatism. Astigmatism requires the proper orientation of a toric curve on the back of the lens relative to the eye. Because the additional power cylinder also must align properly, it is not practical to maintain an inventory of multi-focal lenses. Multi-focal lenses therefore generally are produced by grinding and polishing a semi-finished blank.
Competition in this segment of the lens manufacturing and distribution market is largely based on the ability to produce high-quality specialty lenses while attempting to minimize the time and labor involved. There is a need, therefore, for a flexible, high-speed specialty lens manufacturing process that can produce lenses in an efficient manner.
The present invention thus provides an apparatus for manufacturing a lens with a predetermined prescription from a number of lens molds, a gasket, and a source of a fluid material. The apparatus includes a means for selecting a first lens mold and a second lens mold based upon the prescription, a means for positioning the lens molds within the gasket, a means for inserting an amount of the fluid material within the gasket and between the molds, a means for curing the fluid material so as to form the lens, and a means for advancing the lens molds along a predetermined path through the selecting means, the positioning means, the fill means, and the cure means. The apparatus also may include a control system for operating the selecting means, the positioning means, the fill means, and the cure means.
Specific embodiments of the present invention may include the use of a personal computer with the control system. The control system further may include a database and a data input and output means.
The selecting means may include a conveyor advancing along the predetermined path with one or more transport pallets positioned thereon. The selecting means also may include a storage carousel for storing the lens molds and an automated access arm for transporting the lens molds from the storage carousel to the pallet on the conveyor. The access arm may be a pick and place arm. The access arm may include a gantry, a number of gripper heads, and a number of gripper arms for gripping the lens molds. Each of the gripper heads may include an optical device for reading the indicator. The optical device may include a fiber optic sensor. The fiber optic sensor confirms that the lens mold is in the gripper arms.
The positioning means may include a positioning station with an optical device. The lens molds may have a tic mark or a positioning mark thereon. The optical device may be a camera-based vision system so as to view the tic mark positioned on the lens molds. The optical device may be positioned within a positioning stage. The positioning stage may rotate the lens molds according to the viewed position of the tic mark. The positioning means also may include an assembly station with a retractable assembly stage positioned within a gasket mount. The assembly stage inserts the first lens mold within the gasket at a predetermined depth and then inserts the second lens mold within the gasket at a second predetermined depth. The positioning means also may include a gasket supply with a number of the gaskets.
The positioning means may include one or more access arms for maneuvering the first lens mold, the second lens mold, and the gasket therethrough. A first access arm may position the lens molds on the positioning station, a second access arm may maneuver the lens molds between the positioning station and the assembly station, and a third access arm may maneuver the gasket between the gasket supply and the assembly station and also remove the lens molds and the gasket from the assembly station. The access arms may move along a gantry. Each access arm may have a pair of gripper arms for gripping the lens molds and the gasket.
The inserting means may include one or more fill stations with a needle for piercing the gasket and a variable speed pump for delivering the fluid material. The inserting means also may include one or more cure stations with one or more radiation sources. The radiation sources may be ultraviolet light or visible light sources. Shutters may cover the radiation sources. The shutters may operate independently of one another to provide variable cure cycles from the front and the back.
The present invention may further include a means for removing the lens and the lens mold from the gasket. The removing means may include a pair of movable degasketing arms for stretching the gasket and an extendable plunger for pushing the lens and the lens molds out of the gasket. The invention may further include a means for separating the lens and the lens mold via a number of heating and cooling stations. The invention may further include a means for coating the lens with a scratch resistant treatment, a means for verifying the prescription of the lens, and a means for cleaning the lens molds.
A further embodiment of the present invention may provide a device for identifying and orienting a lens mold as the mold advances along a conveyor positioned along a predetermined path. The lens mold may have an identification indicator thereon and a positioning mark thereon. The device may include an access arm to grasp the lens mold, an optical device to read the identification indicator and the positioning mark, and a printer to print a further indicator on the lens mold at a predetermined location thereon. The device may further include a control system for controlling the access arm, the optical device, and the printer. The optical device may include a bar code reader to read the indicator and a camera-based vision system to view the positioning mark. Alternatively, the bar code could be read by the camera-based vision system. The access arm includes one or more gripper arms such that the gripper arms can grasp and rotate the lens mold. The printer may be an ink jet printer.
The method of the present invention provides a method for manufacturing a lens with a predetermined prescription from a number of lens molds, a gasket, and a source of a fluid material. The method includes the steps of selecting a first mold and a second mold based upon the predetermined prescription, advancing the first lens mold along a predetermined path, positioning the first lens mold within the gasket, advancing the second lens mold along the predetermined path, positioning the second lens mold within the gasket, advancing the first lens mold, the second lens mold, and the gasket along the predetermined path, inserting a predetermined amount of the fluid material within the gasket and between the lens molds, and curing the fluid material so as to form the lens based upon the predetermined prescription.
A further embodiment of the present invention provides a storage and retrieval station for use with a number of lens molds for making lenses. The storage and retrieval station may have a control system, a conveyor controlled by the control system, a storage rack for storing the lens molds positioned adjacent to the conveyor, and an access arm controlled by the control system for transporting a predetermined lens mold from the storage rack to the conveyor. The access arm may have an optical device thereon so as to confirm that the access arm has picked up one of the lens mold from the storage rack. The storage rack may include a rotatable storage carousel. The control system controls the rotatable storage carousel in coordination with the access arm. The access arm may include a gantry, a gripper head, and a pair of gripper arms so as to acquire the predetermined lens mold. The optical device may include a fiber optic sensor.
A further embodiment of the present invention provides an assembly apparatus for positioning a first lens mold and a second lens mold into a gasket so as to form a lens of a predetermined prescription. The lens molds each may include a positioning mark thereon. The apparatus may further include an positioning station for detecting the positioning mark, a gasket supply with the gasket therein, an assembly station for positioning the first lens mold and the second lens mold within the gasket, and an access arm system for transporting the first lens mold, the second lens mold, and the gasket along the predetermined path. The assembly apparatus further may include a control system for operating the positioning station, the assembly station, and the access arm system.
The positioning station may include an optical device for viewing the positioning mark on the lens mold. The optical device may include a camera-based vision system. The positioning station also may include a positioning stage surrounding the optical device. The positioning station may rotate the lens molds as directed by the control system based upon the view of the positioning mark.
The assembly station may include a gasket mount sized to support the gasket and an assembly stage positioned within the gasket mount. The assembly stage may position the first lens mold and the second lens mold into the gasket at a depth as determined by the control system. The positioning of the molds may be based upon the predetermined prescription. The access arm system may include a gantry and a number of access arms. The first access arm may position the lens molds on the positioning station, the second access arm may maneuver the lens molds between the positioning station and the assembly station, and the third access arm may maneuver the gasket between the gasket supply and the assembly station and also may remove the lens molds and the gasket from the assembly station. Each of the access arms may include a number of gripper arms to grip the lens molds and the gasket.
A further embodiment of the present invention may include a device for filling a mold with a fluid material and curing the fluid material. The device may include a fill station with a pump and an insertion device and a cure station with a number of radiation sources and a number of shutters. Each of the shutters may operate independently of one another. A control system may control the fill station and the cure station. The insertion device may include a non-coring needle. The pump may include a multispeed positive displacement pump. The radiation sources may be ultraviolet light sources, visible light sources, or infrared light sources. A movable bracket may maneuver the molds between the fill station and the cure station.
A further embodiment of the present invention may provide a device for removing a gasket from around a mold. The gasket may have a number of support brackets. The device may have a plunger capable of movement in a first direction and a number of degasketing arms surrounding the plunger. The degasketing arms may be capable of movement in a second direction. The degasketing arms may include a number of gripper arms to grip the support brackets of the gasket such that the degasketing arms stretch the gasket in the second direction while the plunger forces the mold out of the gasket in the first direction. The device may further include a control system for controlling the plunger, the degasketing arms, and the gripper arms. An access arm may remove the mold from the plunger.
Other objects, features, and advantages of the present invention will become apparent upon reading the following detailed description of the invention when taken in conjunction with the drawings and the appended claims.